Precision mechanical assemblies, particularly sealed assemblies, can include a number of mating or contacting surfaces where controlled pressure needs to be uniformly applied in order to optimize performance of the precision mechanical assembly and avoid distortion or misalignment of components in the assembly.
Resilient materials such as gaskets, O-rings and seals of various kinds need to be compressed uniformly in order to ensure sealing. If a compressive force that is too small is applied to part of a mating surface, the resilient materials will not conform adequately to a sealing surface, and a leak will result. If a compressive force that is too large is applied to part of a mating surface, the surface itself can warp, and again a leak will result.
Various precision moving parts need to be clamped or secured by use of a controlled compressive force, however, excessive amounts of compressive force can warp moving parts and the resulting misalignment with other parts can cause malfunctions. In particular, magnetic storage devices such as disc drives require precisely controlled pressure patterns between contacting surfaces in order to securely align components and provide air tight seals. It is found, however, that production equipment can go out of adjustment, resulting in rejection of products on the assembly line.
A method and apparatus are needed that can set compressive forces to control pressure patterns in mass production of precision assemblies. Embodiments of the present invention provide solutions to these and other problems, and offer other advantages over the prior art.